dkl = {{(-1 + y)/4, (1 - y)/4, (1 + y)/4, -(1 + y)/4}, {(-1 + x)/4, -(1 + x)/4, (1 + x)/4, (1 - x)/4}} dkm = {{-0.25, 0.25, 0.25, -0.25}, {-0.25, -0.25, 0.25, 0.25}} dkj = {{-2*x, 0.}, {0., -2*y}} nnode = 4 ndofn = 2 ndof = 8 numint = 4 BFcont = 1 bfdof = 2 sha=.25*{{(1-x)*(1-y),(1+x)*(1-y),(1+x)*(1+y),(1-x)*(1+y)}}